Filter retaining device



Nov. 18, 1969 v. w. CIRRINCIONE R 26,715

FILTER RETAINING DEVICE Original Filed April 16, 1962 IN VEN TOR.VINCENT W. CIRRINCIONE ATTORNEY United States Patent 26,716 FILTERRETAINING DEVICE Vincent W. Cirrincione, Rochester, N.Y., assignor toAndex Corp., Rochester, N.Y., a corporation of New York Original No.3,225,680, dated Dec. 28, 1965, Ser. No.

340,580, Jan. 8, 1964, which is a continuation of application Ser. No.187,846, Apr. 16, 1962. Application for reissue Dec. 14, 1966, Ser. No.607,353

Int. Cl. A47j 31/06 US. Cl. 99-312 6 Claims Matter enclosed in heavybrackets I, appears in the original patent but forms no part of thisreissue specification; matter printed in italics indicates the additionsmade by reissue.

ABSTRACT OF THE DISCLOSURE A filter sheet for coflee grounds for usewith a percolator. The sheet is square with a central aperture and anaperture at each 0 the corner areas. The sheet, with the coffee therein,is placed in the percolator cu with the corners folded and the aperturesthreaded over the percolator tube. The corner areas have smallperforations to permit free flow of water.

This application is a continuation of my application Serial No. 187,846,filed April 16, 1962, now abandoned.

This invention relates to filtering devices and more particularly to afilter and coffee ground retainer for use within a conventionalhousehold coffee percolator.

A primary object of this invention is to provide a disposable filter foruse within the perforated coffee strainer of a conventional coffeepercolator, which filter securely retains therein the coffee groundsduring and after percolation.

A further object is to provide a filter composed of a material whichpossesses a high degree of wet strength and yet filters efficiently andeffectively, so that coffee may be produced, having a desirable flavor,without containing any sediment or grounds.

A still further object of this invention is to provide a filter, of thetype described, which can be easily installed in the perforated strainerof a conventional coffee percolator and which can be just as easilyremoved without rupturing after the percolation is complete.

A further object of this invention is to provide a filter, of the typedescribed, which can be inexpensively manufuctured.

Other objects and advantages of my invention will be set forth in theclaims and will be apparent from the following description, when takenin connection with the accompanying drawings, in which:

FIGURE 1 is an elevational sectional view of the filter mounted in anoperative position.

FIGURE 2 is a plan view of the filter.

FIGURE 3 is a plan view of a modified form of a filter.

FIGURE 4 is a plan view of a further modified form.

The device contemplated by this invention is preferably used inconjunction with a conventional coffee pereolator, which is providedwith a perforated container or strainer 5. The strainer 5 contains aplurality of perforations or holes 6. Although these holes 6 arerelatively small, nevertheless a considerable number of coffee groundsand sedimentation may, in the normal course of operation, seep into thecoffee storage pot normally located below the strainer 5. The coffeepercolator is usually provided with a percolator tube 7, which isinsertable into the strainer 5 and which supports the strainer 5 bymeans of a flange 8. The percolator tube 7 is, of course, hollow Re.26,715 Reisswed Nov. 18, 1969 'ice and has an open top 9, through whichthe percolating coffee is discharged.

The device contemplated by this invention constitutes a filter 10, whichis preferably of a clover leaf design. The filter 10 is normallyfabricated from a porous type of thin tissue, having a high degree ofwet strength and capable of fast filter action. The filter 10 isprovided with indentations 11 along each side thereof. It is furtherprovided with a central opening 12 and apertures 13, located in eachcorner. The apertures 13 are formed by means of radial slits 14. Thecentral opening 12 and the apertures 13 have the same approximatediameter as that of the percolator tube 7. In each corner of the filter10, in the vicinity of the apertures 13, there is provided amultiplicity of tiny pin hole perforations 15.

In operation, the filter 10 is placed within the strainer 5 of aconventional percolator such that the tube 7 extends through the centralopening 12. The desired quantity of coffee is placed within the strainer5. The four corners of the filter 10 are then pulled upwardly andinwardly toward the free end 9 of the percolator tube 7, so that theapertures 13 may be threaded over the free end 9. A relatively secureenclosure is thereby provided for the coffee grounds contained withinthe strainer 5. It will then be noted that there is considerableoverlapping of each edge of the filter 10, so as to prevent any seepageof coffee grounds outside of the enclosure so formed. Due to the factthat the filter 10 is fabricated of tissue which has a fairly constantporosity throughout, and since there is considerable overlapping of theedges of the filter 10 near the free end of the tube 7, it has beendeemed advisable to provide the perforations 15. In this manner, theporosity of the enclosure so formed in the area of the overlapping isthereby increased. The precise location of the perforations 15 and theconfiguration of these perforations may be modified in numerous ways soas to produce various flavors and strengths of coffee. After thepercolation of the coffee is deemed to be complete, the filter 10 isremoved from the strainer 5. This may be accomplished quite easily,since the filter 10 is composed of a material having a high degree ofwet strength. The removal of the enclosure is accomplished such that thecoffee grounds contained therein remain in their confined position andare not spilled during the process. The filter 10 containing the usedcoffee grounds, retained in the enclosure so formed, as previouslydescribed, is then thrown away as is any other disposable item. Thestrainer 5 will be left in a relatively clean condition, such thatlittle washing or rinsing is necessary. It will be discovered that theutilization of the filter 10 makes it possible to use a relatively finegrind of coffee. It is, of course, well recognized that with a finergrind of coffee, a greater quantity of coffee may be produced per poundor unit of weight of coffee grounds.

Although the apertures 13 are provided with radial slits 14, it shouldbe recognized that these radial slits are not absolutely necessary tothe operation of the device. The radial slits, of course, do provide fora tighter enclosure and tend to prevent seepage adjacent to the surfaceof the tube 7 in the vicinity of the free end 9 thereof. Furthermore,the central opening 12 could be provided with radial slits similar tothe slits 14 in the apertures 13.

It is obvious that various configurations of filters can be provided. Asshown in FIGURE 3, a modified form of filter 17 is provided. This filteris essentially the same as the filter 10, except that it is providedwith straight sides 18.

A further modified form of filter is disclosed in FIG- URE 4, which isalso essentially the same as the filter shown in FIGURE 2. This modifiedform is provided with square corners 19. Clearly, there are many otherpossible configurations which would function in essentially the samemanner as previously described. The particular configuration or shape offilter selected would depend upon the particular type of coffeepercolator employed. However, the configuration disclosed in FIG- URE 2herein may be successfully used in most conventional coffee percolators.

Having thus described my invention, I claim:

1. A filter and coffee ground retainer device for in stallation within acoffee percolator having a strainer and a centrally located fluiddelivery percolator tube therein consisting in its entirety of a sheetof porous filter material, said sheet having a high degree of wetstrength and being foldable to define an enclosure capable of holdingand retaining ground coffee which enclosure and ground coffee may bedisposed of as a unit, said sheet having a smooth, flat planar surfacethroughout and being of substantially square configuration with anopening in the center thereof, each corner of said sheet terminating ina rounded edge portion to eliminate excess material from said sheet informing said enclosure, each corner having an aperture formed thereinspaced inwardly from said rounded edge towards said center opening, eachof said corners provided with a multiplicity of pierced perforationssurrounding said aperture with the greatest number of said perforationsbeing between said aperture and center opening, said sheet beingpositionable within said strainer with said tube extending through saidcenter opening, said corners being foldable towards said tube to form anenclosure for coffee grounds with said tube being threaded through saidapertures and said corners overlapping one another with the rounded edgeof one corner overlapping only a portion of the perforations between theaperture and the center opening of the diametrically opposite corner toimprove the porosity of the overlapping portion of said sheet ofmaterial and permitting the ready passage therethrough of the fluid fromsaid tube whereby a smooth and even distribution of the fluid isobtained over the coffee grounds in said enclosure.

2. A filter and coffee ground retainer device for installation within acoffee percolator having a strainer and a centrally located fluiddelivery percolator tube therein consisting in its entirety of a sheetof porous filter material, said sheet having a high degree of wetstrength and being foldable to define an enclosure capable of holdingand retaining ground coffee which enclosure and ground coffee may bedisposed of as a unit, said sheet being of substantially squareconfiguration with an opening in the center thereof, each side edge ofsaid sheet having an indentation provided in the center thereof todefine a plurality of corner segments, each corner segment terminatingin a rounded edge, each corner segment having an aperture formed thereinspaced inwardly from said rounded edge towards said center opening, eachof said corner segments provided with a multiplicity of perforationssurrounding said aperture with the greatest number of said perforationsbeing between said aperture and said center opening, said sheet beingpositionable within said strainer with said tube extending through saidcenter opening, said corner segments being foldable towards said tube toform an enclosure for coffee grounds with said tube being threadedthrough said aperture and said corner segments overlapping one anotherwith the rounded edge of one segment overlapping only a portion of theperforations between the aperture and the center opening of thediametrically opposite corner segment to improve the porosity of saidsheet of material and permitting the ready passage through theperforations of the corner segments of the fluid from said tube wherebya smooth and even distribution of the fluid is obtained over the coffeegrounds in said enclosure and said indentations and rounded cornerseliminating excess portions of said sheet and providing for a neat andcompact arrangement of said corner segments during the overlappingthereof.

3. A filter sheet for use in a coflee percolator cup to wrap aroundground coffee contained therein, said sheet being substantially squareand having a central area adapted to lie on the bottom of a percolatorcup and a central aperture adapted to be threaded over a percolator tubeextending up through the center of the cup, said central area beingotherwise imperjorare except for the filtering characteristics of thesheet, and an aperture in each of the corner areas, all of saidapertures being adapted to be closely threaded over the percolator tubeof a coffee percolator cup, said sheet having a group of relativelysmall perforations in each of the corner areas only to permit free flowof water therethrough.

4. A filter sheet (1S set forth in claim 3 haring the corners removed toeliminate unnecessary impediment to the entry of water t/terethrough.

5. A filter sheet us yet forth in claim 3 having the sides thereofnotched centrally thereof to facilitate folding of the corners over oneanother in wrapping ground coflee contained on a filter sheet having itscentral area disposed in a coffee percolator cup.

6. A filter sheet as set forth in claim 3 having the corners removed andthe side edges centrally notched.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the original patent.

UNITED STATES PATENTS 1,352,232 9/1920 Weightman et al. 53-207 X1,481,757 1/1924 Stokes 53-207 X 1,489,807 4/1924 Anderson 992952,859,684 11/1958 Polizzi 210496 X 3,083,100 3/1963 Baran 993l2 X SAMIHN. ZAHARNA, Primary Examiner US. Cl. X.R. 2l0282

